This invention relates to an ejection system for ejecting an ejection seat/airman combination from an aircraft.
With certain aircraft designs, and certain seating arrangements for airmen in aircraft equipped with ejection systems of the kind to which the invention relates, it is sometimes necessary to ensure that, in operation of the ejection system in an emergency, the seat/airman combination will follow a predetermined curved trajectory on ejection from the aircraft.
Such a requirement may arise, for example, where the seats for two crew members of an aircraft are disposed side by side in the aircraft so that it is necessary to ensure that, on ejection, the two seats, with their respective airmen, follow divergent trajectories so that there is no risk of collision between the seat/airman combination and the two seat/airman combinations are widely separated when parachute deployment takes place.
A similar requirement may also, for example, arise where it is necessary to ensure clearance, on ejection, with respect to any part of the aircraft structure, or even where the configuration of the aircraft makes it necessary for a seat/airman combination (normally after being tilted from the normal upright position) to be ejected initially in a horizontal or inclined direction relative to the normal orientation of the aircraft prior to moving upwardly.
In British Patent Specification No. 941,683, there is disclosed and claimed an ejection system for ejecting an ejection seat/airman combination from an aircraft, comprising an ejection gun for effecting initial ejection of the combination from the aircraft in a predetermined direction relatively to the aircraft and at least one primary rocket motor independent of said ejection gun for accelerating the combination in said predetermined direction by producing a thrust vector aligned, or substantially aligned, with said predetermined direction and extending through or substantially through, the centre of gravity of the combination, the system further comprising at least one auxiliary rocket motor adapted to produce thrust in a direction such as to cause variation of the flight path of the combination produced by the operation of said ejection gun and said primary rocket motor.
Whilst the system disclosed and claimed in British Patent Specification No. 941,683 can, at least in certain cases, produce a desired curved trajectory of a seat/airman combination on ejection, this is accompanied by a spinning or yawing movement of the combination which is disadvantageous, both as regards the control of the trajectory itself, and as regards subsequent deployment of the parachute effectively and rapidly.